0X (1976) Note: title is commonly listed as OX ("oh-ex"), but should be 0X (Arabiczero·Romanten). (Chapter 16: "'I am speaking for 0X,' the computer said. 'This is the code designation Zero X, or Arabic numeral nothing multiplied by the Roman numeral ten'")
Books 1–3 were collected as Of Man and Manta (1986).
Books 1–3 were collected as The Magic of Xanth (1981) // Three Complete Xanth Novels / The Quest for Magic, while books 4–6 were collected as The Continuing Xanth Saga.
This was originally written as single novel in continuity with the Cluster series, which takes place decades later, but was split up due to length at the behest of the publisher, Jove.[2]
God of Tarot (1979)
Vision of Tarot (1980)
Faith of Tarot (1980)
Tarot (1987) The series omnibus as a single novel as originally intended
Through the Ice (1989) with Robert Kornwise posthumously—Kornwise was a high school student who had died. His friends sent his unfinished manuscript and a plea to Piers Anthony to help their deceased friend get published. To make sure that the book was a fitting memorial tribute, Piers Anthony made sure it was printed on acid-free paper despite the expense.
The Caterpillar's Question (1992) with Philip José Farmer—This collaboration was actually the result of another proposed collaborative project. The original idea proposed by an editor was to have a book where each chapter was written by a different author. That project fell apart, but Piers Anthony and Philip José Farmer later decided they wanted to salvage something from it by morphing it into a two-person collaboration, where the two alternated chapters, without revealing who wrote which chapters.
Quest for the Fallen Star (1998) with James Richey and Alan Riggs
Dream a Little Dream (1998) with Julie Brady
Realty Check (1999)
The Secret of Spring (2000) with Jo Anne Taeusch
The Gutbucket Quest (2000) with Ron Leming
Starkweather: Immortal 0 (2007) with David A. Rodriguez—This collaboration is a different one for Piers Anthony. He crafted an original short story based on the character Cartaphilus from the creator-owned Starkweather comic book series by David A. Rodriguez. This short story was then adapted into a comic book script and painted by fantasy artist Patrick McEvoy and published by Archaia Studios, making Starkweather: Immortal issue 0, Piers Anthony's first true comic book work.
Lava from the Chronology Anthology (2015) published by Curiosity Quills Press[5]
In the Shadow of the Song from the Darkscapes Anthology (2017) published by Curiosity Quills Press
Relationships series
Relationships (2006), republished in 2007 by Phaze Books[6]
Relationships, Vol. 2 (2007), published by Phaze Books
Relationships, Vol. 3 (2008), published by Phaze Books
Relationships 4 (2010), published by Phaze Books
Relationships 5 (erotic stories) Phaze 2012; Dreaming Big to come
Relationships 6 Dreaming Big 2018
Relationships 7 Dreaming Big 2019
Relationships 8 to come
Nonfiction
Bio of an Ogre (1988): the autobiography of Piers Anthony to age 50
Letters to Jenny (1994): The mother of a teenage fan wrote to Piers Anthony about her daughter Jenny, the victim of a drunk driver, being paralyzed and in a coma. The mother felt that having letters from Jenny's favorite author read to her might help bring her out of her coma. He wrote her constantly and for a long period of time, even naming a Xanth character after her. Jenny eventually came out of her coma, but remains paralyzed and has difficulty communicating. This book is a collection of the letters from the first year of correspondence.
How Precious Was That While (2001): an autobiography of Piers Anthony to age 65
Alfred (2007): a biography of the author's father, Alfred Jacob, as told by the women in his father's life
Piers Anthony's Visual Guide to Xanth (Harper, 1989), by Piers Anthony and Jody Lynn Nye. Illustrated by Todd Cameron Hamilton and James Clouse. ISBN0-380-75749-4.